Version 3.4.0b2 Announcement

Zope 3.4.0 beta 2 Released!

November 5, 2007 - The Zope 3 development team announces the Zope 3.4.0b2 release.

This release is the second beta release for Zope 3.4.0. It was preceeded by an early beta 1 release back in July.

Zope 3.4 introduces support for binary large objects in the ZODB, and provides a new postprocessing hook for publishing results. Many of the packages also provide small feature improvements that are too numerous to list at this point.

Packages and Eggs

Since the first Zope 3.4 alpha and beta releases, we have finished the transition to a completely egg-based system. This largely means that most Zope 3 developers do not use the classic Zope 3 tar ball release anymore. However, for your convenience, the Zope 3 developers will provide the classic Zope 3 tar ball releases for at least the 3.4 series and probably for 3.5 as well.

So how are Zope 3 applications built using only eggs?

The Known Good Set (KGS)

The known good set -- or in short KGS -- is a package index that derives from the official Python Package Index (PyPI) and thus contains all available packages in the Python world. But for a controlled set of packages, only certain versions that are known to work together are available. The list of controlled packages and their versions for Zope 3.4 can be found at the index page [1].

The index can be used in several ways -- described here for buildout-based projects. The easiest method is to specify the index option in your buildout.cfg file:

index =

You can also "nail" the versions by downloading the versions [2] and insert them as follows:

versions = versions

zope.interface = 3.4.0

zopeproject Project Builder

Philipp von Weitershausen has developed a package called zopeproject to quickly setup the boilerplate for any Zope 3 based project. Ample documentation is provided at the zopeproject home page [3]. zopeproject uses Paste or ZDaemon to create a working server. Here are the necessary commands to get a project started:

$ easy_install zopeproject
$ zopeproject HelloWorld
$ cd HelloWorld
$ bin/helloworld-ctl foreground

Demo Packages

At this point, there is no demo package demonstrating a simple Zope 3 application setup. (I hope one gets developed before Zope 3.4.0 final.) However, the z3c.formdemo package can be used as a fairly minimal setup. To get started with it, do the following:

$ svn co svn:// formdemo
$ cd formdemo
$ python
$ ./bin/buildout -v
$ ./bin/demo fg

What is Zope 3?

Zope 3 is a web application server that continues to build on the heritage of Zope. It was rewritten from scratch based on the latest software design patterns and the experiences of Zope 2.

The component architecture is the very core of Zope 3 that allows developers to create flexible and powerful web applications.

Compatibility with Zope 2

Zope 3 is not upwards compatible with Zope 2. This means you cannot run Zope 2 applications in Zope 3.

We continue to work on the transition from Zope 2 to Zope 3 by making Zope 2 use more and more of the Zope 3 infrastructure. This means that new code written in Zope 2 can benefit from Zope 3 technology. Also, with care, code can be written that works in both Zope 3 and Zope 2. This allows a Zope 2 application to slowly evolve towards Zope 3. Unchanged Zope 2 applications are never expected to work in Zope 3, however.


Installation instructions for both Windows and Un*x/Linux are now available in the top level README.txt file of the distribution. The binary installer is recommended for Windows.

Zope 3.4 requires Python 2.4.4 to run. You must also have zlib installed on your system.



Much thanks to everyone who contributed to this release. Since all contributions are now spread over a multitude of packages, listing all contributors is not feasible anymore.